Databases are present in many aspects of the modern world. These databases exist as a way for those who have data, the data releasers, to provide the data to those who want or need the data, the data users. The distribution of data can happen in many different forms, from providing the data over an internet link, over a local area network, over a cellular network as a file, by e-mail . . . etc.
Presently this kind of data distribution database is mostly in the form of single tier, i.e. there is only one central database, as shown in FIG. 1. Operation of data distribution and verification is centralized to the central database for process, which may bring about the following defects.
First, data distribution and verification is processed in the central database, which calls for high requirement of both the central database concurrent processing capacity and the network broadband.
Second, there is a very high requirement for timeliness in data verification process. If the network connection between the data releaser and the central database is not stable, it will take a long time to get the result of data verification.
Third, data use efficiency is low. Normally a data releaser will release data of certain use value exclusively to those data users with whom the data releaser has certain relation, while other data users and other data releasers cannot gain access to such data, thus resulting in low data use efficiency.
Fourth, the data verification reliability is low. The use value of some data can be realized only once. Should such data be obtained by a malicious user and presented to the data releaser, the data releaser would only be able to verify such data rather than the user who presents the data. Thus normal users would be deprived of the use value of the data.